-LRB- CNN -RRB- -- Skeletal remains found near an Arizona campground are believed to be those of a missing 2-year-old , the Yavapai County Sheriff 's Office said Tuesday .

Sylar Newton was reported missing July 25 from the Beaver Creek Campgrounds in Rimrock . Authorities said last week that the boy was presumed dead as they announced the launch of a criminal investigation into his disappearance .

The remains were found Tuesday afternoon at the bottom of a wash less than two miles from the campground , the sheriff 's office said . The office said the remains `` likely came to rest in this area due to recent flash flooding . ''

`` At this time , the remains are believed to be that of Sylar Newton , but final confirmation is still pending , '' the sheriff 's office said .

Sylar was last seen shortly after midnight July 24 , sleeping in a tent with his family at the campgrounds . About 1:45 a.m. July 25 , the family noticed that he was missing from his sleeping bag .

`` The sheriff 's office believes Sylar did not wander from the campground and he is presumably dead , '' Yavapai County Sheriff Steve Waugh told a news conference last week . `` The search effort is now in a recovery mode and the investigation has become criminal in nature . ''

Sylar was camping with his custodial mother , Christina Priem , and her children , when he disappeared . Priem has said she was in the process of adopting the boy from his biological mother .

Sheriff 's spokesman Dwight D'Evelyn said last month that `` there 's no evidence '' that the planned adoption played a role in his disappearance , `` but until we 've exhausted every lead , all possibilities are being investigated . ''

About 25 other people were at the campground the night of Sylar 's disappearance -- all of whom have cooperated with investigators , according to the sheriff 's office .

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Sylar Newton was reported missing from a campground July 25

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Remains were found Tuesday less than two miles from the camping site

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Final confirmation is pending , authorities say